When transferring energy from himself to the Dalki's body that Quinn was currently in. He made sure not to overdo it for a few reasons. The first there was simply no need to. The power of a two spike was simply too much for any one spike to deal with. This was something that could be used to their advantage because even though Quinn had the power of a two spike, two spikes did not appear on his body.
However, there was still Vincent who was outside roaming close to the camp. During the testing the energy that was transferred to the Dalki body would eventually be returned, but if he was to take up too much energy, it would only make his body weaker. At the end of the day, the Dalki could die, but Quinn's original body could not.
